get on my nerves

22/04/2015
ASNR 2015: Skull Base Symposium
“Get On My Nerves: Dysphagia, Dysarthria, Hoarseness and Ptosis”
Sunday April 26, 2015
7:45-9:15 am
The Patient with
Glossopharyngeal
Neuralgia
Disclosures
None
http://childcarefirstaid.ca/ear-injuries-signs-symptoms-causes-and-treatment/
Nancy J. Fischbein, MD
Stanford Neuroradiology
fischbein@stanford.edu
http://www.coloribus.com/adsarchive/prints/angino-rub-throat-drops-nail-3424555/
Glossopharyngeal Neuralgia
Learning Objectives
• An uncommon CN hyperactivity-pain syndrome
• Define the syndrome of glossopharyngeal
neuralgia
• Briefly review anatomy of CN IX, the
glossopharyngeal nerve
• Discuss pathologies that are associated with
the clinical entity of GPN
• Severe, transient, sharp pain in ear, base of
tongue, tonsillar fossa, or beneath angle of jaw
– Occurs in adults, esp females >50 yrs, L>R
– Distribution of auricular and pharyngeal branches of
glossopharyngeal (IX) and vagus (X) nerves
– Commonly provoked by swallowing, talking or coughing
• Specific trigger zone can be difficult to identify
– 0.2-1.3% of facial pain syndromes; ~2% bilateral
• Can be associated w cardiac arrhythmia or
syncope (2-3% of cases)
– Called “vagoglossopharyngeal neuralgia”
– Pain followed by bradycardia/asystole
– Related to circuit interconnections between CN’s IX, X
GPN: Abbreviated History
• 1910: severe pain in distribution of glossopharyngeal
nerve described (patient had a CPA tumor)
• 1920: syndrome rx’d w extracranial nerve avulsion
• 1921: current nomenclature of “GPN” introduced
• 1926, 1927: rx w intracranial sectioning of nerve;
continued into 1970’s
• 1977: Laha, Jannetta: observed nerve compression
by vertebral artery and proposed rx w microvascular
decompression (MVD)
• 2015: medical rx (AED’s), MVD are mainstay
– Rx of underlying lesion if identified
CN IX: Glossopharyngeal Nerve
Modality
Function
General
Sensory
Afferent
Somatic sensory
information from
parts of ear,
posterior 1/3 of
tongue, soft palate,
upper pharynx,
mastoid region
Visceral
Afferent
Visceral sensory
information from
carotid body, carotid
sinus
Special
Afferent
Taste from posterior
1/3 tongue
Special
Visceral
Efferent
Branchial motor to
stylopharyngeus
muscle
General
Visceral
Efferent
Visceral motor
(parasympathetic) to
parotid gland
Relevant
branches:
tympanic, tonsillar,
lingual, carotid,
pharyngeal
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Proximity of CN 9, CN 10
Diagnostic Criteria for Classic GPN
• CN IX, X are in close anatomical proximity as they
exit the medulla and traverse the cerebellomedullary
cistern en route to the jugular foramen (JF)
• A. Paroxysmal attacks of pain lasting from a fraction
of a second to 2 minutes
• B. Pain has the following characteristics:
– Anastomoses exist between rootlets of the nerves
– Also shared nuclei in lower pons and medulla
– 1. Unilateral location
– 2. Distribution within posterior part of tongue, tonsillar
fossa, pharynx, or beneath angle of lower jaw and/or ear
– 3. Sharp, stabbing and severe
– 4. Precipitated by swallowing, chewing, talking, coughing,
and/or yawning
• C. Attacks are stereotyped in the individual patient
• D. No clinically evident neurological deficit
• E. Not attributed to another disorder
Ozveren et al, Neurosurgery 52: 1400-1410, 2003
International Headache Society, http://www.ihs-classification.org
Netter: http://www.nature.com/gimo/contents/pt1/full/gimo2.html
Imaging Evaluation
Criteria for “Symptomatic” GPN
• Etiology typically NV compression
• Includes pain as defined for classic GPN
with the proviso that aching pain may persist
between paroxysms and sensory
impairment may be found in the districution
of the glossopharyngeal nerve
– So looking for an impinging vessel,
typically PICA, vs AICA or vertebral a
• MR is study of choice
– High-resolution heavily T2-weighted
images to assess basal cisterns
– CTA can contribute as well
• High-resolution; relationship of vessels to
bony anatomy
• CT portion useful to assess for Eagle
syndrome
• Examples of causative lesions: CPA or JF
tumor, carotid space lesion, UADT
malignancy, leptomeningeal disease,
brainstem lesion (MS), Eagle syndrome
Normal Imaging Anatomy: CT
•
•
•
•
•
CN IX, X exit medulla
Traverse CM cistern to
pars nervosa (IX) or pars
vascularis (X) of jugular
foramen
Below SB: carotid space
CN IX exits anteriorly at
NP level to pharynx
CN X continues into
thorax, abdomen
Jacobson nerve
• Gadolinium to assess for
inflammation, infection, neoplasm
Ghanta, Neurol India v60, 2012
Normal Imaging Anatomy: MR
Pars
nervosa
CN IX
IPV
Glossopharyngeal n
Vagus n
Bony septum
MO
CN X
Post meningeal
CN XI
Pars vascularis
Arnold nerve
Moon, AJNR v30; 2009.
http://spinwarp.ucsd.edu/NeuroWeb/Anatomy/tmp-1.html
From superior to inferior
Coronal
Jugular spine
Jugular spine
Rhoton/Buza, J Neurosurg v42, 1975
• MRA may help evaluate vessels
– Additionally, a causative lesion has been
demonstrated
Pars nervosa
Sagittal
Pars nervosa
IPV
Pars vascularis
Pars vascularis
IJV
Red=CN9; Blue=CN10
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Glossopharyngeal Neuralgia: Cases
33 F w paroxymal pain in R pharynx, ear
Neurovascular compression is by far the most
common cause, but multiple pathologies have been
associated w GPN
• Brainstem lesions:
– Infarction, demyelination, tumor, hemorrhage
– More typically give mult CN palsies, not GPN
• Cisternal lesions
– Tortuous vessel vs aneurysm or AVM
– Leptomeningeal tumor, nerve sheath tumor
• Jugular foraminal lesion
– Nerve sheath tumor, meningioma, metastasis
• Carotid space lesion/extracranial lesion
– Consider Eagle syndrome
70 F w increasingly frequent episodes
of R ear and pharyngeal pain
Dx: neurovascular compression by PICA, eventually rx’d w MVD
80 M w intermittent R pharyngeal pain
65 M w occasional ear pain
Dx: R PICA aneurysm. Patient currently
considering treatment options.
Dx: presumed CN IX schwannoma
55 F w R ear fullness and pharyngeal
pain as well as increasing dysphagia and
hoarseness. A middle ear mass was
present on otoscopic examination.
Dx: arachnoid cyst
63 F w h/o breast cancer and new headaches as well as lower cranial nerve
palsies. Though the patient complained of minor throat pain, she did not have
classic symptoms of glossopharyngeal neuralgia.
Dx: leptomeningeal carcinomatosis.
Dx: meningioma. Biopsied, then
rx’d w Cyberknife radiosurgery
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69 M, progressive lower CN dysfunction, Horner syndrome, unrelenting pain in R ear,
neck and throat
Eagle Syndrome
• Uncommon sequel of abnl
elongation (>3 cm) and/or
ossification of stylohyoid
ligament
– Symptoms include recurrent
throat pain + anterolateral neck
pain, w referred pain to ear
– Presumed due to compression
of neurovascular structures in
neck
Dx: metastatic poorly differentiated carcinoma. Patient subsequently expired due
to tumor progression and aspiration pneumonia.
Treatment of Classic GPN
• Medical: carbamazepine, gabapentin,
phenytoin
• Surgical: microvascular decompression
– Rhizotomy as a back-up procedure
• Other: glossopharyngeal nerve block,
antidepressants, opioids, steroids, RF nerve
ablation, stereotactic radiosurgery (target:
distal portion of CN IX, X at jugular foramen)
• Often included in ddx of GPN
• Typically rx’d surgically
Summary
• GPN is an uncommon pain syndrome in the
head and neck
• Typical etiology is neurovascular
compression
• Imaging is performed not only to assess for
neurovascular compression but also to
exclude alternative etiologies and to assist
with treatment planning
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Horner’s Syndrome
Learning Objectives
• Review the anatomy of the Occulosympathetic
pathway (OSP)
• Learn to localize lesion based on clinical findings
• Learn pathology encountered at various levels in the
OSP
Deborah L Reede M.D.
Professor and Chair Department of Radiology
SUNY Downstate Medical Center
Introduction
Horner’s Syndrome (HS) occurs when there is
interruption of the oculosympathetic pathway
(OSP). The clinical symptoms may cause little if
any functional impairment in most patients.
However, since both benign and malignant
disease processes are associated with HS a
thorough clinical evaluation is required.
Anatomy of the OSP
• Consists of three neurons:
• FON - Posterolateral
hypothalamus
• SON - Ciliospinal center
(C8-T2)
• TON - Superior cervical
ganglion (C2-C3)
First Order Neuron (FON)
Second Order Neuron (SON)
• Location: posterolateral
hypothalamus
• Location: Ciliospinal Center
of Budge Waller
• Course: PGF descend in the
reticular formation
(brainstem, cervical and
thoracic cord) to synapse in
the intermediolateral (IML)
gray substance of the spinal
cord at level C8-T2
(Ciliospinal center of BudgeWaller)
• Course: PGF exit in the
ventral spinal root, pass
through the inferior cervical
ganglion or stellate ganglion
(fusion of inferior cervical
and first thoracic ganglion)
and middle cervical ganglion
in route to the TON in the
superior cervical ganglion.
1
Third Order Neuron (TON)
• Location: SCG
OS Innervation
IPSILATERAL
• PGF travel with the ICA for a
short distance to the
cavernous sinus where they
attach to CN VI then to V1
and enter the SOF (via the
ophthalmic nerve ON). The
long posterior cilliary nerve a
branch of the ON innervates
Muller’s muscles and the
dilator muscles of the iris.
• PGF travel with the ECA to
the blood vessels to the face
and are responsible for
sweating.
• Sweat glands body and face
• Dilator muscles of the iris
• Retractor muscles of the eyelids
Clinical Findings
Ptosis
• Muller’s muscle - in the upper
eye lid is a thin smooth muscle
arising from the undersurface
of the levator palpebrae
superioris muscle
• This muscle elevates the upper
eyelid and controls the resting
position of the upper eyelid
(when the eye is open)
• Innervated by the sympathetic
nervous system. Interruption of
the sympathetic nerve supply
results in a moderate droop of
the upper lid (ptosis)
Classic Triad
Ptosis
Miosis
Anhydrosis
Ptosis of the left upper eyelid
Miosis
Decrease in pupil size due to paralysis of the dilator muscles.
The sphincter and dilator muscles of the iris are innervated by
the autonomic nervous system.
Sympathetic and Parasympathetic
Innervation of the Iris
When the sympathetic innervation is interrupted the
parasympathetic innervation of the sphincter muscle is
unopposed, therefore the pupil constricts.
Innervation
Sympathetic - Sphincter
Parasympathetic - Dilator
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Anhydrosis
• Lack of sweat production due to interruption of the
sympathetic innervations of the sweat glands
Other Clinical Findings
• Conjunctival hyperemia
• Upside down ptosis
• Unilateral absence of sweat to the forehead, face, or
body is a good indication of Horner’s syndrome
• Iris Heterochromia
• Harlequin Sign
Transient Early Signs of Acute
Horner’s Syndrome
Conjunctival hyperemia
Sympathetic denervation causes vasodilatation of
the capillaries in the conjunctiva (“blood shoot
eyes”)
Iris Heterochromia
• The iris is blue or gray at birth.
An intact OSP is required for
pigmentation of the iris to
develop in the first year of life.
• Lesions interrupting the OSP in
the first year of life lead to iris
heterochromia (light colored
iris)
Iris heterochromia is noted on the
patient’s right. Miosis and ptosis
(of both the upper and lower eye
lids) are also present.
Upside Down Ptosis
• Best demonstrated when the
upper lid is in the resting
position
• Sympathetic fibers innervate
retractor muscle fibers (Muller’s
muscle) in the lower lid.
• The lower lid will rise slightly in
Homer’s Syndrome (“upside
down” ptosis)
• This, in conjunction with the
upper lid changes causes
narrowing of the palpebral
fissure and may give the false
appearance of enopthalmus
Harlequin Sign
• Unilateral facial flushing seen in
children with congenital HS
• Areas that do not flush
correspond with areas of
anhidrosis
• Decrease skin temperature on
the affected side
• Due to impaired vasodilatation
3
HS Classification
• Preganglionic HS
– lesion proximal to the
superior cervical
ganglion
• Postganglionic HS
– lesion anywhere from the
superior cervical
ganglion to the eye
Preganglionic HS
Proximal to the SCG
- Central (FON HS): from the
hypothalamus to the lower
cervical to upper thoracic cord
before the PGF synapse with
the SON
- Peripheral (SON HS): lesion
located anywhere from the
SON to before the PGF
synapse with the TON in the
superior cervical ganglion
Postganglionic HS
• TON HS
• Caused by lesions that
occur anywhere from the
SCG to the eye
Anisocoria
• Anisocoria (unequal pupil size) may be due to a number of
causes i.e. aging, sympathetic or parasympathetic
dysfunction
• Examination in the dark will help determine the etiology
Clinical Evaluation
Dilation Lag
• The sympathetic denervated pupil dilates slower than the
normal pupil in the dark
• This is best identified when photographs are taken after 5
and 15 seconds in the dark
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Pharmacological Testing
• Ideally sequential pharmacological testing using
cocaine (5-10% solution) and hydroxyamphetamine
(1% solution) should be performed
• Poor response to cocaine confirms the diagnosis of
HS
• Response to hydroxyamphetamine helps determine if
the Horner’s is pre or postganglionic
5 - 10% Cocaine
• If the sympathetic pathway
is intact, norepinephrine is
released from the nerve
innervating the dilator
muscles
• Normal pupil – dilates
• Horner’s - poor response
Apraclonidine can be
used instead of cocaine
to confirm the diagnosis
of HS.
Pupil dilates and the eye lid elevates
Hydroxyamphetamine
• Releases norepinephrine from
the postganglionic nerve
endings to the dilator muscles
• Preganglionic Horner’s (FON
and SON) pupil dilates
• Postganglionic Horner’s (TON),
pupil will not dilate because
norepinephrine is depleted from
the nerve endings
• Cocaine inhibits the uptake of
HO therefore wait at least 24 to
72 hours to insure maximum
sensitivity to HO
First Order Neuron
Horner’s Syndrome
Central Preganglionic HS
First Order Neuron HS
First Order Neuron HS
• Lesion location: from the
hypothalamus to the
Ciliospinal Center of Budge
Waller (C8-T2) before the
PGF synapse with the SON
• Least common location of
Preganglionic HS
Clinical Findings
• Miosis may be the only
evidence of a central
Homer's Syndrome
• Usually present with
cerebellar or brain stem
findings
• Anhydrosis Distribution
ipsilateral entire half of the
body
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First Order Neuron HS
First Order Neuron HS
Imaging Modalities
Etiologies
• Brain stem infarcts - Lateral medullary syndrome
(Wallenberg Syndrome)
•
FON HS with brain or brain stem symptoms:
Brain MR +/-MRA , diffusion weighted imaging
• Tumor (hypothalamus, brain stem, or spinal cord)
•
• Trauma
• Inflammation (poliomyelitis, transverse myelitis)
FON HS with myelopathic features:
Cervical and Upper Thoracic Spine MR
• Syringomyelia
• Demyelinating disease i.e. Multiple sclerosis
First Order Neuron HS
First Order Neuron HS
Hypothalamic Pilocytic Astrocytoma
LMP (Wallenberg)
BB
T1 POST
• Most common cause of FON HS
• Occlusion of the PICA or the vertebral artery can
produce infarct in the region
• CN palsies and FON HS
First Order Neuron HS
Syringohydromyelia
Intramedullary cyst that contain CSF can causes compression
of the gray and white matter. HS may alternate from eye to
eye.
T1 POST
T2
13 yr old boy with headaches and left anisocoria.
Pharmacological testing suggested a left preganglionic HS.
First Order Neuron HS
Multiple Sclerosis
The presence of HS in a patient with a history of
demyelinating disease such as MS suggest the
possibility of spinal cord involvement. MS plaques
tend to occur in the dorsolateral aspect of the cord.
This is where the sympathetic fibers travel in the cord.
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First Order Neuron HS
Multiple Sclerosis
Second Order Neuron
Horner’s Syndrome
Peripheral Preganglionic HS
Second Order Neuron HS
Second Order Neuron HS
Second Order Neuron HS
• Lesion location: from the SON
to before the PGF synapse
with the TON
• The majority of cases of
Preganglionic HS are
secondary to lesions in this
region.
Second Order Neuron HS
Clinical Findings
• Often have the full
syndrome of ptosis, miosis,
and anhidrosis
• May have a brachial plexus
palsy
• Anhidrosis distribution:
ipsilateral face and neck
Second Order Neuron HS
Etiologies
• Surgery or trauma of the thorax and neck
• Pancoast tumor
• Primary spinal nerve root tumors or lesions
compressing or destroying the nerve root
(osteophytes and nerve root avulsions)
• Sympathetic chain lesions (neoplasm and
surgery)
• Neck masses (nodal disease or primary neck
masses such as an enlarged thyroid)
Imaging
• Lesions can be located in the SON, nerve
roots of C8- T2 or neck up to the level of C2C3
• If a mass is present on PE or a lesion is seen
the lung apex on a CXR – usually do a CT
covering the area of interest
• If clinical findings suggest spine or nerve root
involvement - MR
• Otherwise you need to cover the area from
C2- C3 to T2
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Second Order Neuron HS
Pancoast Tumor
Second Order Neuron HS
Brachial Plexus and Sympathetic Ganglion
• Non small cell bronchogenic
carcinomas (squamous or
adenocarcinoma)
• Located in the lung apex
(superior sulcus)
• Cause SON HS secondary to
inferior cervical ganglion
involvement and brachial
plexopathy when the inferior
trunk of the brachial plexus is
involved
Second Order Neuron HS
Pancoast Tumor
Second Order Neuron HS
Sympathetic Ganglion Schwannoma
G
*
*
19 yr old male with a right preganglionic HS.
58-year-old male with weight loss, right brachial
plexopathy and preganglionic HS
Second Order Neuron HS
Cervical Sympathetic Chain (CSC)
The CSC runs longitudinally over the longus colli and capitis muscles,
posteromedial to the CS, deep to the prevertebral fascia. Lesions
involving the CSC typically cause anterior or anterolateral
displacement of the CS.
Second Order Neuron HS
Sympathetic Schwannoma (SCS)
Nerve sheath tumors can arise from the sympathetic chain. HS may
be part of the initial presentation but is more often encountered after
surgery for the removal of the lesion.
Infrahyoid SCS
*
*
*
M CSCS causing
anterolateral displacement of
the CS structures.
Suprahyoid SCS
T1
T2
T1
POST
*
*
*
SCS causes anterolateral
displacement of the
carotids and splays them
from the internal jugular
vein.
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Second Order Neuron HS
Second Order Neuron HS
Neuroblastoma
Neuroblastoma
Arises from the neural crest blast cells in the adrenal
gland or cervical sympathetic chain. Less than 5% of
these lesion occurs in the neck. These lesion should be
look for in children who present with HS, iris
heterochromia and no history of cervical trauma.
PD
POST
2 yr old male with a right preganglionic HS, iris
heterochromia and no history of birth trauma.
Second Order Neuron HS
Second Order Neuron HS
Goiter
Metastatic Breast Carcinoma
Any lesion that compresses the sympathetic chain can
produce a HS.
M
35 yr old female with a thyroid mass and a left
preganglionic HS
50 yr old female with breast cancer had a left
preganglionic HS.
Third Order Neuron HS
Third Order Neuron HS
Third Order Neuron
Horner’s Syndrome
Postganglionic HS
• Lesions can be
located anywhere
from the from the
SCG to the eye
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Third Order Neuron HS
Third Order Neuron HS
Clinical Findings
• Full syndrome usually present: ptosis, miosis
and anhydrosis
• Orbital lesions: proptosis, chemosis and
conjunctival hyperemia are often present
• Cavernous sinus: ipsilateral extraocular
pareses esp CN VI without brain stem signs
• Carotid dissection: hx of trauma, neck pain,
ipsilateral vision loss and acute onset of
postganglionic HS
Third Order Neuron HS
Anhidrosis
• Ipsilateral face and
neck if the lesions
occurs in the SCG
• Ipsilateral nose and
forehead if the lesions
is distal to the SCG
Third Order Neuron HS
Anhidrosis
• Ipsilateral face and neck if the
lesions occurs in the SCG
• Ipsilateral nose and forehead
if the lesions is distal to the
SCG , because sympathetic
fibers travel with the IAC to
this region.
Third Order Neuron HS
Etiologies
•
•
•
•
•
Carotid dissection above the SCG
FMD
Cluster or Migraine headache
Trauma
Neoplasm/ infection in the orbit,
pericarotid and cavernous sinus regions
Third Order Neuron HS
Imaging
Fibromusculardysplasis
• NO ASSOCIATED CLINICAL FINDINGS
NO IMAGING
• If clinical findings are focal, the scan
should cover the suspected area
• If history suggest a carotid dissection,
CT/CTA or MR/MRA
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Third Order Neuron HS
Third Order Neuron HS
Carotid Dissection
Nasopharyngeal Carcinoma
Carotid dissection should be r/o if a pt has a hx of
trauma, neck pain, ipsilateral vision loss and acute
onset of postganglionic HS
T1FS
T1FS
High signal around the left ICA with an eccentric flow void.
46-year-old Chinese female with left TON HS.
Third Order Neuron HS
Summary
Invasive Aspergillosis
Before this lecture what lesions would you have
list as potential causes of HS ?
s
45-year-old immune compromised male, presented with
left proptosis, chemosis, conjunctival hyperemia and left
postganglionic HS.
Chest Radiologist
Pediatric Radiologist
Pancoast tumor
Birth trauma
Neuroblastoma
Neuroradiologist
LMP infarct
Carotid dissection
Summary
Now you know there is more to HS
“THAN MEETS THE EYE”
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Last but not least:
Cranial XI and XII
XI and XII
Anatomy where are the nerves
Denervation patterns
XI
XII
Pathology
Primary
Secondary invasion
Perineural spread
Carotid dissection
Other
XI Accessory
XII Hypoglossal
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Landmarks
Pars Nervosa (medial jugular foramen)
Jugular spine
Jugular tubercle (occipital)
Hypoglossal canal
Landmarks
Carotid artery
Jugular
Posterior triangle fat
Digastric muscle
Glosso-Mylohyoid gap
XI
Spinal accessory n. crosses anterior to the jugular vein
most commonly but occasionally posterior. Gives of branches
to the Sternocleidomastoid before extending to the Trapezius
XII
Hypoglossal n. initially follows the carotid artery then
curves anteriorly passing lateral to the internal and external
carotid. The nerve is medial to the digastric muscle and
passes through the glosso-mylohyoid gap between the
hyoglossus m. and mylohyoid into the sublingual space and
tongue.
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Denervation patterns
XI
SCM and Trapezius
XII
Tongue muscles
spares mylohyoid and digastric
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Accessory
SCM
Trapezius
MBC
Etiology of denervation
Accessory
SCM
Trapezius
Radical Neck Dissection
SCM
Jugular Vein
CN XI
Fat
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Carotid dissection
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Perineural spread
Perineural spread
Perineural spread
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Persistent hypoglossal artery
Venous Varix
Artwork by Robert Galla
1.Janfaza P. Surgical anatomy of the head and neck. 1st Harvard University
Press ed. Cambridge, Mass.: Harvard University Press, 2011.
2.Murakami R, Baba Y, Nishimura R, et al. MR of denervated tongue: temporal
changes after radical neck dissection. AJNR American journal of
neuroradiology. 1998;19(3):515-8.
3.Murakami R, Baba Y, Nishimura R, et al. CT and MR findings of denervated
tongue after radical neck dissection. AJNR American journal of
neuroradiology. 1997;18(4):747-50.
4.Rhoton AL, Rhoton AL, Congress of Neurological Surgeons. Rhoton cranial
anatomy and surgical approaches. Philadelphia: Lippincott Williams &
Wilkins, 2003.
5.Som PM, Curtin HD. Head and Neck Imaging - 2 Volume Set Expert ConsultOnline and Print. 5th ed. Philadelphia: Mosby Imprint
Elsevier - Health Sciences Division., 2011; p. 3080 p.
6.Verdalle P, Herve S, Kossowski M, et al. Spontaneous dissection of the
internal carotid artery in its extracranial portion, revealed by a hypoglossal
paralysis: report of four cases. The Annals of otology, rhinology, and
laryngology. 2001;110(8):794-8.
Meningocele
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